On Sat, Jan 29, 2011 at 1:53 PM, Ted Ts'o <ty...@mit.edu> wrote: > On Fri, Jan 28, 2011 at 07:37:02AM +0100, Olaf van der Spek wrote: >> >> Is there a way to log cases where (potentially) unsafe writes happen? >> Cases like truncation of an existing file, rename on a target that's >> not yet synced, etc. > > Not really, because there are plenty of cases where it's perfectly OK > not to sync a file on close or on rename. Any files created during a > build, for example, can easily be reproduced in the unlikely case of a > systme crash. If you are untaring a source tree, it's fine not to > worry about syncing out the files, since presumably you can always > repeat the untar operation. Or take git; when git is checking out > files into the working directory, there's no reason that has to be > done in a super-safe way. On the other hand, when it is writing the > git object files and pack files, those had better be done safely. At > the end of the day the application programmer needs to understand what > is going on, and write his code appropriately based on the needs of > his application with respect to reliability after a power crash. > > So how can you just log warnings that the program has just done > something unsafe? It's unsafe only if there's no other way to > reconstitute the data that was just written. But that's not something > which is easily knowable.
If all potentially unsafe cases could be logged, the log can be analyzed by a human to detect the real unsafe cases such that the developers of those apps can be notified and the apps can be fixed. -- Olaf -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/aanlktimbiodsp4qndcozcnp1yr_6rnxjmw7xtdvgs...@mail.gmail.com
